Hemodynamic data pattern in patients with acute pancreatitis

Intravenous fluid therapy in patients with severe acute pancreatitis admitted to the intensive care unit: a narrative review

Patients with acute pancreatitis (AP) often require ICU admission, especially when signs of multiorgan failure are present, a condition that defines AP as severe. This disease is characterized by a massive pancreatic release of pro-inflammatory cytokines that causes a systemic inflammatory response syndrome and a profound intravascular fluid loss. This leads to a mixed hypovolemic and distributive shock and ultimately to multiorgan failure. Aggressive fluid resuscitation is traditionally considered the mainstay treatment of AP. In fact, all available guidelines underline the importance of fluid therapy, particularly in the first 24–48 h after disease onset. However, there is currently no consensus neither about the type, nor about the optimal fluid rate, total volume, or goal of fluid administration. In general, a starting fluid rate of 5–10 ml/kg/h of Ringer’s lactate solution for the first 24 h has been recommended. Fluid administration should be aggressive in the first hours, and continued only for the appropriate time frame, being usually discontinued, or significantly reduced after the first 24–48 h after admission. Close clinical and hemodynamic monitoring along with the definition of clear resuscitation goals are fundamental. Generally accepted targets are urinary output, reversal of tachycardia and hypotension, and improvement of laboratory markers. However, the usefulness of different endpoints to guide fluid therapy is highly debated. The importance of close monitoring of fluid infusion and balance is acknowledged by most available guidelines to avoid the deleterious effect of fluid overload. Fluid therapy should be carefully tailored in patients with severe AP, as for other conditions frequently managed in the ICU requiring large fluid amounts, such as septic shock and burn injury. A combination of both noninvasive clinical and invasive hemodynamic parameters, and laboratory markers should guide clinicians in the early phase of severe AP to meet organ perfusion requirements with the proper administration of fluids while avoiding fluid overload. In this narrative review the most recent evidence about fluid therapy in severe AP is discussed and an operative algorithm for fluid administration based on an individualized approach is proposed.

Ethyl pyruvate treatment ameliorates pancreatic damage: evidence from a rat model of acute necrotizing pancreatitis

INTRODUCTION

Ethyl pyruvate (EP), a natural flavoring and fragrance agent, has been shown to exert anti-inflammatory and antioxidant actions. We tested the potential beneficial effects of EP in a rat model of acute necrotizing pancreatitis (ANP), a serious condition with a significant inflammatory explosion and oxidative stress.

MATERIAL AND METHODS

Fifty-two adult male Sprague-Dawley rats were divided into four groups: sham + saline, sham + EP, ANP + saline, and ANP + EP. The ANP was induced by glycodeoxycholic acid and cerulein. Animals were sacrificed at 48 h and biochemical, hematological, and histological markers of ANP and inflammation were assessed. The extent of mortality, systemic cardiorespiratory variables, pancreatic microcirculation, renal/hepatic functions, acinar cell injury and enzyme markers for pancreas and lung tissues were investigated.

RESULTS

The EP-treated ANP group presented significantly lower mortality than the untreated ANP group (44% (7/16) vs. 19% (3/16), respectively, p < 0.05). Administration of EP resulted in significantly lower levels of IL-6 (ANP + saline: 5470 ±280 vs. ANP + EP: 2250 ±180 pg/ml, p < 0.05). Compared with the ANP group, the ANP + EP group had a lower pancreatic necrosis score (1.45 ±0.2 vs. 0.96 ±0.2, p < 0.05). Moreover, intraperitoneal EP administration had a positive effect on most indices of pancreatitis (amylase and alanine transaminase levels) and lung damage (except lung malondialdehyde levels) as they decreased towards baseline values.

CONCLUSIONS

The results from this experimental study indicate that EP, a nontoxic chemical approved by the Food and Drug Administration as a food additive, provides positive effects on the course of pancreatitis, suggesting potential usefulness in management of ANP.

The association between portal system vein diameters and outcomes in acute pancreatitis

BACKGROUND/OBJECTIVES

Acute pancreatitis (AP) progresses to necrotizing pancreatitis in 15% of cases. An important pathophysiological mechanism in AP is third spacing of fluids, which leads to intravascular volume depletion. This results in a reduced splanchnic circulation and reduced venous return. Non-visualisation of the portal and splenic vein on early computed tomography (CT) scan, which might be the result of smaller vein diameter due to decreased venous flow, is associated with infected necrosis and mortality in AP. This observation led us to hypothesize that smaller diameters of portal system veins (portal, splenic and superior mesenteric) are associated with increased severity of AP.

METHODS

We conducted a post-hoc analysis of data from two randomized controlled trials that included patients with predicted severe and mild AP. The primary endpoint was AP-related mortality. The secondary endpoints were (infected) necrotizing pancreatitis and (persistent) organ failure. We performed additional CT measurements of portal system vein diameters and calculated their prognostic value through univariate and multivariate Poisson regression.

RESULTS

Multivariate regression showed a significant inverse association between splenic vein diameter and mortality (RR 0.75 (0.59-0.97)). Furthermore, there was a significant inverse association between splenic and superior mesenteric vein diameter and (infected) necrosis. Diameters of all veins were inversely associated with organ failure and persistent organ failure.

CONCLUSIONS

We observed an inverse relationship between portal system vein diameter and morbidity and an inverse relationship between splenic vein diameter and mortality in AP. Further research is needed to test whether these results can be implemented in predictive scoring systems.

Characterization of Cardiac Dysfunction by Echocardiography in Early Severe Acute Pancreatitis

OBJECTIVE

Persistent organ failure is a feature of severe acute pancreatitis (SAP) and the leading cause of death. Although usually defined by hypotension, cardiovascular dysfunction (CD) in early SAP has not been well characterized. We aim to characterize CD in patients with SAP and hypotension and determine its impact on clinical outcome.

METHODS

Patients with SAP and hypotension were studied to define the frequency, nature, and prognostic significance of CD characterized by echocardiography and classified as systolic, diastolic, or combined dysfunction.

RESULTS

Of the 72 patients (median age, 41 years, 44 men), 10 (14%) had percutaneous drain placement, 12 (17%) underwent surgery, and 14 (19%) died. Persistent hypotension was present in 58 (81%) and transient hypotension in 14 (19%) patients. Cardiovascular dysfunction was present in 47 (65%) patients: 28 (60%) with diastolic dysfunction, 8 (17%) with systolic dysfunction, and 11 (23%) with combined dysfunction. Left ventricular end diastolic volume, stroke volume index, cardiac index, and diastolic dysfunction correlated with mortality on univariate analysis.

CONCLUSIONS

Two thirds of patients with early SAP and hypotension had cardiac dysfunction, which was most commonly diastolic dysfunction. A better understanding of the nature of cardiac dysfunction in this setting may allow more accurate diagnosis, prognostication, and management.

Effects of glutamine alone on the acute necrotizing pancreatitis in rats

BACKGROUND

The effects of the glutamine on the acute pancreatitis are controversial in the clinical and experimental studies. The aim of this study was to investigate the influence of glutamine alone on acute necrotizing pancreatitis (ANP) induced by glycodeoxycholic acid in rats.

MATERIAL AND METHODS

Fifty-two male Sprague-Dawley rats weighing 300-350 g were used. Rats were divided into four groups as sham + saline, sham + glutamine, ANP + saline and ANP + glutamine. ANP in rats was induced by glycodeoxycholic acid. The extent of acinar cell injury, mortality, systemic cardiorespiratory variables, functional capillary density, renal/hepatic functions, and changes in some enzyme markers for pancreatic and lung tissue were investigated during ANP in rats.

RESULTS

The induction of ANP resulted in a significant increase in the mortality rate, pancreatic necrosis, and serum activity of amylase, alanine aminotransferase, interleukin-6, lactate dehydrogenase in bronchoalveolar lavage fluid, serum concentration of urea, and tissue activity of myeloperoxidase and malondialdehyde in the pancreas and lung, and a significant decrease in concentrations of calcium, blood pressure, urine output, pO2, and functional capillary density. The use of glutamine alone improved these changes.

CONCLUSIONS

Glutamine demonstrated beneficial effect on the course of ANP in rats. Therefore, it may be used by itself in the treatment of acute pancreatitis.

Effects of 17ß-Estradiol on the Acute Necrotizing Pancreatitis after Onset in Rats

The aim of this study was to investigate the influence of 17ß-estradiol (E2) on acute necrotizing pancreatitis (ANP) induced by glycodeoxycholic acid in rats. Rats were divided into six groups as sham + saline, sham + single dose E2 (SDE2), sham + multiple dose E2 (MDE2), ANP + saline, ANP + SDE2, and ANP + MDE2. ANP in rats was induced by glycodeoxycholic acid. The extent of acinar cell injury, mortality, systemic cardiorespiratory variables, functional capillary density (FCD), renal/hepatic functions, and changes in some enzyme markers for pancreatic and lung tissue were investigated during ANP in rats. The induction of ANP resulted in a significant increase in the mortality rate, pancreatic necrosis, and serum activity of amylase, alanine aminotransferase (ALT), interleukin (IL)-6, lactate dehydrogenase (LDH) in bronchoalveolar lavage (BAL) fluid, serum concentration of urea, and tissue activity of myeloperoxidase (MPO) and malondialdehyde (MDA) in the pancreas and lung, and a significant decrease in concentrations of calcium, blood pressure, urine output, p02, and functional capillary density (FCD). The use of E2 did not alter these changes. E2 demonstrated no effect on the course of ANP in rats. Therefore, it has no value in the treatment during acute pancreatitis.

[Fluid therapy in acute pancreatitis]

Severe acute pancreatitis (AP) is associated with an increased need for fluids due to fluid sequestration and, in the most severe cases, with decreased peripheral vascular tone. For several decades, clinical practice guidelines have recommended aggressive fluid therapy to improve the prognosis of AP. This recommendation is based on theoretical models, animal studies, and retrospective studies in humans. Recent studies suggest that aggressive fluid administration in all patients with AP could have a neutral or harmful effect. Fluid therapy based on Ringer's lactate could improve the course of the disease, although further studies are needed to confirm this possibility. Most patients with AP do not require invasive monitoring of hemodynamic parameters to guide fluid therapy administration. Moreover, the ability of these parameters to improve prognosis has not been demonstrated.

Effects of clotrimazol on the acute necrotizing pancreatitis in rats

This study aims to investigate the influence of clotrimazol (CLTZ) on acute necrotizing pancreatitis (ANP) induced by glycodeoxycholic acid in rats. Rats were divided into five groups as sham + saline, sham + CLTZ, sham + polyethylene glycol, ANP + saline, and ANP + CLTZ. ANP in rats was induced by glycodeoxycholic acid. The extent of acinar cell injury, mortality, systemic cardiorespiratory variables, functional capillary density (FCD), renal/hepatic functions, and changes in some enzyme markers for pancreatic and lung tissue were investigated during ANP in rats. The use of CLTZ after the induction of ANP resulted in a significant decrease in the mortality rate, pancreatic necrosis, and serum activity of amylase, alanine aminotransferase, interleukin-6, lactate dehydrogenase in bronchoalveolar lavage fluid, serum concentration of urea, and tissue activity of myeloperoxidase, and malondialdehyde in the pancreas and lung and a significant increase in concentrations of calcium, blood pressure, urine output, pO2, and FCD. This study showed that CLTZ demonstrated beneficial effect on the course of ANP in rats. Therefore, it may be used in the treatment of acute pancreatitis.

Diastolic dysfunction, prolonged QTc interval and pericardial effusion as predictors of mortality in acute pancreatitis

BACKGROUND AND AIM

The cardiac changes in acute pancreatitis have been earlier studied but the data on their prognostic significance is limited. This study was done to determine electrocardiographic (ECG) and echocardiographic changes in acute pancreatitis and determine their prognostic significance.

METHODS

Fifty-two consecutive patients (mean age 36.5 ± 11 years (44 males)) with acute pancreatitis and without prior cardiovascular comorbidites were prospectively enrolled and subjected to clinical, laboratory and radiological investigation. ECG and echocardiography was done at admission and during follow up.

RESULTS

Seventeen patients (32.7%) had mild pancreatitis and 35 (67.3%) patients had severe pancreatitis. Sinus tachycardia was the most common ECG abnormality. QTc prolongation was seen in 30/52 (57.7%) patients. On echocardiography, no patient had systolic dysfunction but 31/52 (59.6%) patients had diastolic dysfunction. All 22 patients with QTc interval < 440 ms survived compared with 8/30 patients with QTc interval ≥ 440 ms who died (P = 0.01). All eight patients who died had evidence of diastolic dysfunction (100%). None of the patients without diastolic dysfunction succumbed to illness (P = 0.02). Pericardial effusion was present in 6/52 (11.5%) patients. Of the eight patients who died, pericardial effusion was present in three (37.5%) patients and this frequency was significantly higher than that in patients who recovered (3/44 [6.8%]; P = 0.04).

CONCLUSION

Electrocardiographic and echocardiographic changes are seen in more than 50% of patients with acute pancreatitis. Prolonged QTc interval, pericardial effusion and diastolic dysfunction are associated with higher mortality.

Honokiol attenuates the severity of acute pancreatitis and associated lung injury via acceleration of acinar cell apoptosis

Severe acute pancreatitis remains a life-threatening disease with a high mortality rate among a defined proportion of those affected. Apoptosis has been hypothesized to be a beneficial form of cell death in acute pancreatitis. Honokiol, a low-molecular-weight natural product, possesses the ability of anti-inflammation and apoptosis induction. Here, we investigate whether honokiol can ameliorate severe acute pancreatitis and the associated acute lung injury in a mouse model. Mice received six injections of cerulein at 1-h intervals, then given one intraperitoneal injection of bacterial lipopolysaccharide for the induction of severe acute pancreatitis. Moreover, mice were intraperitoneally given vehicle or honokiol 10 min after the first cerulein injection. Honokiol protected against the severity of acute pancreatitis in terms of increased serum amylase and lipase levels, pancreas pathological injury, and associated acute lung injury. Honokiol significantly reduced the increases in serum tumor necrosis factor-α, interleukin 1, and nitric oxide levels 3 h and serum high-mobility group box 1 24 h after acute pancreatitis induction. Honokiol also significantly decreased myeloperoxidase activities in the pancreas and the lungs. Endoplasmic reticulum stress-related molecules eIF2α (phosphorylated) and CHOP protein expressions, apoptosis, and caspase-3 activity were increased in the pancreas of mice with severe acute pancreatitis, which was unexpectedly enhanced by honokiol treatment. These results suggest that honokiol protects against acute pancreatitis and limits the spread of inflammatory damage to the lung in a severe acute pancreatitis mouse model. The acceleration of pancreatic cell apoptosis by honokiol may play a pivotal role.

Cardiovascular manifestations of acute pancreatitis

Acute pancreatitis (AP) is an acute inflammatory process of the pancreas that is associated with variable involvement of pancreatic/peripancreatic tissue and one or more organ systems in varying degrees. Among the multiple organ system dysfunctions in severe AP, cardiovascular and/or pulmonary manifestations are frequent. The cardiovascular system may be affected alone or with other organ systems in all stages of AP. Abnormalities of cardiac rhythm, contractility, and vasomotor tone of peripheral vessels are common cardiovascular manifestations. The pathogenetic factors of cardiac manifestations include hypovolemia and metabolic disturbances (eg, hyperkalemia, hypomagnesemia, and hypophosphatemia). Clinically, patients present with hypotension, tachycardia, and signs of systemic inflammatory response syndrome (high cardiac index, significant pulmonary shunting, decreased systemic vascular resistance, and decreased myocardial contractility). Approximately 50% of patients with AP have electrocardiographic changes, most commonly T-wave flattening and ST-segment depression. Many of the cardiac manifestations in AP are reversible with appropriate management. In AP, early onset of either multi-organ dysfunction or a sustained single-organ dysfunction is associated with poor outcome. This review highlights cardiac manifestations of AP relevant to clinical practice.

Acute pancreatitis and critical illness: a pancreatic tale of hypoperfusion and inflammation

Since it was first widely recognized at the end of the 19th century, acute pancreatitis has proven a formidable clinical challenge, frequently resulting in management within critical care settings. Because the early assessment of severity is difficult, the recognition of severe acute pancreatitis (SAP) and the implementation of critical care treatment precepts often are delayed. Although different management strategies for life-threatening features of SAP have been debated for decades, there has been little recent reduction in mortality rates, which can be as high as 30%. This article discusses severity designation at the time of diagnosis, reviews the pathophysiologic mechanisms so well characterized by the noxious combination of severe systemic inflammation and hypoperfusion, and provides a management algorithm that parallels current critical care strategies.

Effects of caffeic acid phenethyl ester on pancreatitis in rats

BACKGROUND

This study investigated the effect of caffeic acid phenethyl ester (CAPE) on acute necrotizing pancreatitis (ANP) induced by glycodeoxycholic acid in rats. CAPE, an active component of honeybee propolis, has previously been determined to have antioxidant, anti-inflammatory, antiviral, and anticancer activities.

MATERIALS AND METHODS

Forty-eight rats were divided into four groups of 12. Group 1 animals received intraductal saline and intravenous saline infusion treatment. Group 2 was given intraductal saline and intraperitoneal CAPE infusion treatment. ANP was induced in the animals in group 3 (ANP with saline infusion), and group 4 had induced ANP plus CAPE infusion treatment (ANP with CAPE infusion). Sampling was performed 48 h after treatment.

RESULTS

ANP induction significantly increased mortality rate, pancreatic necrosis, and bacterial infection in pancreatic and extrapancreatic organs. ANP also increased levels of amylase and alanine aminotransferase (ALT) in serum, increased levels of urea and lactate dehydrogenase in bronchoalveolar lavage fluid (BAL LDH), increased the activities of myeloperoxidase (MPO) and malondialdehyde (MDA) in pancreas and lung tissue, and decreased the serum calcium levels. The use of CAPE did not significantly reduce the mortality rate but significantly reduced the ALT and BAL LDH levels, the activities of MPO and MDA in the pancreas, the activity of MDA in the lungs, and pancreatic damage. The administration of CAPE did not reduce the bacterial infection.

CONCLUSIONS

These results indicate that CAPE had beneficial effects on the course of ANP in rats and suggest that CAPE shows promise as a treatment for ANP.

Effects of Enalaprilat on Acute Necrotizing Pancreatitis in Rats

The aim of this study was to investigate the influence of enalaprilat on acute necrotizing pancreatitis (ANP) induced by glycodeoxycholic acid in rats. The induction of ANP resulted in a significant increase in the mortality rate, pancreatic necrosis, serum activity of amylase, alanine aminotransferase (ALT), and interleukin-6 (IL-6), lactate dehydrogenase (LDH) in bronchoalveolar lavage (BAL) fluid, serum concentration of urea, and tissue activity of myeloperoxidase (MPO) and maondialdehyde (MDA) in the pancreas and lung, and a significant decrease in concentrations of calcium, blood pressure, urine output and p0(2). The use of enalaprilat inhibited the changes in urine output, blood pressure, serum concentration of urea, p0(2), and tissue activity of MPO and MDA in the pancreas and lungs. It reduced the mortality and pancreatic damage. Enalaprilat demonstrated a beneficial effect on the course of ANP in rats; therefore, it may be used in the treatment of acute pancreatitis.

Acute Necrotizing Pancreatitis Complicating Uteroplacental Apoplexy

OBJECTIVE

Abruptio placentae induced by acute pancreatitis during pregnancy is very rare. We present a pregnant woman with a series of complications due to acute necrotizing pancreatitis.

CASE REPORT

Presented herein is a 21-year-old, nulliparous woman at 33 weeks' gestation. The initial episode of abdominal pain was thought to be acute appendicitis (which in actuality was identified to be acute pancreatitis) and was complicated with abruptio placentae, uteroplacental apoplexy, and intrauterine fetal demise. Sterile necrotizing pancreatitis was confirmed by computerized axial tomography and total negativity of bacterial cultures taken from blood and ascites during the hospitalization. Nonsurgical management with conservative treatment was employed and the patient recovered gradually.

CONCLUSION

Acute pancreatitis is difficult to diagnose during pregnancy. It presents as a systemic inflammatory response syndrome resulting in hemodynamic changes and may lead to abruptio placentae. Nonsurgical conservative treatment may be useful in such patients.

Diagnostic Dilemma of Sudden Deaths Due to Acute Hemorrhagic Pancreatitis

Sudden death due to acute pancreatitis has been rarely determined. A review of 3305 autopsies performed between 1991 and 2001 at the Council of Forensic Medicine found 12 cases (0.36%) with sudden death due to acute hemorrhagic pancreatitis without symptoms. A history of chronic alcohol ingestion was obtained from family in four cases (33%), and no stones were found in the bile ducts or in the gall bladders. During the autopsies, hemorrhage and edema were localized on the head of the pancreas in three cases and the whole pancreas in nine cases. The most common extrapancreatic pathology was found in the lung including pulmonary edema, alveolar hemorrhage, pleural effusion, and pulmonary congestion. There was no correlation between pulmonary and pancreatic damage. It is suggested that the forensic pathologists who are dealing with sudden unexpected death must not ignore the examination of pancreatic and extrapancreatic regions to avoid missing acute pancreatitis.

Effects of Lazaroid U-74389G on Acute Necrotizing Pancreatitis in Rats

The aim of this study was to investigate the influence of U-74389G on acute necrotizing pancreatitis (ANP) induced by glycodeoxycholic acid in rats. The induction of ANP resulted in a significant increase in mortality rate, pancreatic necrosis, and serum levels of amylase, alanine aminotransferase, interleukin-6, tumor necrosis factor alpha, and urea, in lactate dehydrogenase levels in bronchoalveolar lavage fluid, and in the activities of myeloperoxidase and malondialdehyde in pancreas and lung tissue; a significant decrease was observed in serum calcium levels, blood pressure, urine output, and pO(2). The use of U-74389G inhibited the changes in serum urea, pO(2), and tissue levels of myeloperoxidase and malondialdehyde in pancreas and lungs. Moreover, it indicated a limited effect on the course of ANP in the rats and did not reduce mortality and pancreatic damage. Therefore, it may be used in the treatment of lung injury during acute pancreatitis.

Gastrointestinal disorders of the critically ill. Shock and acute pancreatitis

Shock and pancreatitis are closely associated. Shock can be a sequel of severe pancreatitis and systemic shock may induce pancreatitis. This chapter discusses both features with regard to their clinical and pathophysiological characteristics.

Ultrasonographic splanchnic arterial flow measurement in severe acute pancreatitis

INTRODUCTION

Duplex ultrasonographic technology is now capable of detecting flow signals in the various splanchnic vessels and calculating the concomitant flow velocities using fast-Fourier transformation.

AIM

To use Doppler sonography to investigate how splanchnic hemodynamics vary during the early stage of severe acute pancreatitis.

METHODOLOGY

Six patients with severe acute pancreatitis (age, 59.0 +/- 6.57 years; four men, two women) and seven with mild to moderate acute pancreatitis (age, 60.1 +/- 7.41 years; five men, two women) were examined with Doppler sonography immediately after disease onset. The maximum velocity, minimum velocity, mean velocity, pulsatility index, and resistive index were determined from the Doppler spectra from the proper hepatic artery, celiac artery, and superior mesenteric artery. We also examined 15 healthy subjects (age, 59.3 +/- 4.60 years; 10 men, five women) as controls.

RESULTS

The maximum velocity of the proper hepatic artery in patients with severe acute pancreatitis was significantly higher than that in patients with mild to moderate acute pancreatitis (p = 0.011) and in control subjects (p = 0.0047). Similarly, significant increases in both the minimum velocity and the mean velocity of the proper hepatic artery were observed in patients with severe acute pancreatitis. Neither pulsatility index nor resistive index of the proper hepatic artery showed a significant difference among the three groups. There were no significant differences among the three groups with respect to the flow velocity of the superior mesenteric artery. In contrast, the pulsatility index of the superior mesenteric artery in patients with severe acute pancreatitis was significantly lower than that in patients with mild to moderate acute pancreatitis (p = 0.0058) or in control subjects (p = 0.0024). For patients with acute pancreatitis, a significant inverse correlation was obtained between the maximum velocity of the proper hepatic artery and the pulsatility index of the superior mesenteric artery (r = -0.658, p = 0.0145).

CONCLUSION

The increase in the hepatic arterial flow velocity and the decrease in the superior mesenteric arterial pulsatility index may represent early events of the severe type of acute pancreatitis.

Management of necrotizing pancreatitis

Infection complicating pancreatic necrosis leads to persisting sepsis, multiple organ dysfunction syndrome and accounts for about half the deaths that occur following acute pancreatitis. Severe cases due to gallstones require urgent endoscopic sphincterotomy. Patients with pancreatic necrosis should be followed with serial contrast enhanced computed tomography (CE-CT) and if infection is suspected fine needle aspiration of the necrotic area for bacteriology (FNAB) should be undertaken. Treatment of sterile necrosis should initially be non-operative. In the presence of infection necrosectomy is indicated. Although traditionally this has been by open surgery, minimally invasive procedures are a promising new alternative. There are many unresolved issues in the management of pancreatic necrosis. These include, the use of antibiotic prophylaxis, the precise indications for and frequency of repeat CE-CT and FNAB, and the role of enteral feeding.

Acute necrotizing pancreatitis: treatment strategy according to the status of infection

OBJECTIVE

To determine benefits of conservative versus surgical treatment in patients with necrotizing pancreatitis.

SUMMARY BACKGROUND DATA

Infection of pancreatic necrosis is the most important risk factor contributing to death in severe acute pancreatitis, and it is generally accepted that infected pancreatic necrosis should be managed surgically. In contrast, the management of sterile pancreatic necrosis accompanied by organ failure is controversial. Recent clinical experience has provided evidence that conservative management of sterile pancreatic necrosis including early antibiotic administration seems promising.

METHODS

A prospective single-center trial evaluated the role of nonsurgical management including early antibiotic treatment in patients with necrotizing pancreatitis. Pancreatic infection, if confirmed by fine-needle aspiration, was considered an indication for surgery, whereas patients without signs of pancreatic infection were treated without surgery.

RESULTS

Between January 1994 and June 1999, 204 consecutive patients with acute pancreatitis were recruited. Eighty-six (42%) had necrotizing disease, of whom 57 (66%) had sterile and 29 (34%) infected necrosis. Patients with infected necrosis had more organ failures and a greater extent of necrosis compared with those with sterile necrosis. When early antibiotic treatment was used in all patients with necrotizing pancreatitis (imipenem/cilastatin), the characteristics of pancreatic infection changed to predominantly gram-positive and fungal infections. Fine-needle aspiration showed a sensitivity of 96% for detecting pancreatic infection. The death rate was 1.8% (1/56) in patients with sterile necrosis managed without surgery versus 24% (7/29) in patients with infected necrosis (P <.01). Two patients whose infected necrosis could not be diagnosed in a timely fashion died while receiving nonsurgical treatment. Thus, an intent-to-treat analysis (nonsurgical vs. surgical treatment) revealed a death rate of 5% (3/58) with conservative management versus 21% (6/28) with surgery.

CONCLUSIONS

These results support nonsurgical management, including early antibiotic treatment, in patients with sterile pancreatic necrosis. Patients with infected necrosis still represent a high-risk group in severe acute pancreatitis, and for them surgical treatment seems preferable.

Surgical management of necrotizing pancreatitis

In necrotizing pancreatitis, surgical treatment is indicated in patients with infected necrosis. Conservative management should be favored if necrosis remains sterile and the patient responds to intensive care therapy. Different surgical techniques have been established during the past years, including conventional drainage, open and semiopen drainage, and closed management with postoperative continuous lavage of the lesser sac. For experienced physicians, these techniques provide comparable results, and none has been proved to be superior to the others.

Low systemic vascular resistance: differential diagnosis and outcome

OBJECTIVE: To determine the frequency and prognosis of the various causes of low systemic vascular resistance (SVR). DESIGN: Analysis of consecutive patients over a 5-year period; retrospective review. SETTING: Medical intensive care unit of a large university hospital. PATIENTS: Fifty-five patients with unexplained hypotension and a SVR less than 800 dynes x s/cm5. BACKGROUND: There are minimal data in the medical literature determining the frequency or outcome of patients with a low SVR that is unrelated to sepsis or the sepsis syndrome. We retrospectively reviewed and analyzed all hemodynamic data in a large university hospital over a 5-year period to determine the frequency and prognosis of the various causes of low SVR. Fifty-five patients with unexplained hypotension and a SVR less than 800dynesxs/cm5were identified. MAIN RESULTS: Twenty-two patients (Groups 1 and 2) met the criteria for sepsis syndrome. The mean SVR for this group was 445 +/- 168 dynesxs/cm5 with an associated mortality of 50%. Group 3 contained 20 patients with possible sepsis. Thirteen patients (Group 4) were nonseptic. The mean SVR of this group was 435 +/- 180 dynes x s/cm5 with an associated mortality of 46%. Extremely low SVR (below 450 dynes x s/cm5) was associated with a significantly higher mortality regardless of the etiology. CONCLUSIONS: At least a quarter of patients with hypotension and a low SVR have nonseptic etiologies. The patients with nonseptic etiologies have a similar mortality to septic patients. Clinicians should be aware of the wide spectrum of conditions that induce a low SVR.

The therapeutic effect of hypertonic solutions on the changes in the effective circulating plasma volume in acute necrotizing pancreatitis in rats

While hypovolemia or hypovolemic shock is dominant in the early stage of severe acute pancreatitis, there have been few studies on the effects of hypertonic solutions in the management of this disease. We conducted this study to evaluate the therapeutic effects of hypertonic saline solutions (HS) on the course of severe acute pancreatitis in rats. Pancreatitis was induced in male Wistar rats by injecting a 5% solution of sodium taurocholate into the biliopancreatic duct. The effective circulating plasma volume (ECPV) was measured using radioiodinated [125I]bovine serum albumin. Samples of blood and of ascitic fluid were obtained 3, 6, and 12 h after the onset of pancreatitis. Lactated Ringer's solution (LR) and HS were administered consecutively for 3 h beginning 3 h after the induction of pancreatitis. ECPV was measured 6 h after the onset of pancreatitis. The survival rates were investigated for up to 10 days. The mean ECPV decreased significantly from 24.9 +/- 1.1 ml/kg before disease onset to 11.5 +/- 1.3 ml/kg 6 h postoperatively. LR failed to achieve a normal value for ECPV even following a 150 ml/kg infusion. HS200 and HS300 restored the ECPV to the normal level, and with smaller volumes infused. All rats in the untreated group died within 3 days. LR and HS improved the survival rates, with the infusion of HS200, 100 ml/kg, thus attaining a 45% survival at 10 days.

Endotoxemia predicts outcome in acute pancreatitis

The incidence of complications of acute pancreatitis is high in patients with endotoxemia, and so we determined the endotoxin levels in the blood and peritoneal fluid of patients with acute severe pancreatitis to correlate the levels with any sequelae. Fourteen patients with acute severe pancreatitis were examined with regard to clinical features, biochemical tests, and laparotomy (n = 9). In all coagulation profiles, blood gas analysis, chest and abdominal x-rays, ultrasound, and abdominal computed tomography scan (n = 10) were performed. Qualitative estimation of endotoxin levels was done in peripheral blood and peritoneal and peripancreatic fluid. Ten (71.42%) of 14 patients had endotoxin in the blood, and 9 (64.28%) had it in the peritoneal fluid. Twelve (85.7%) had pulmonary involvement, with hypoxia being the most common (85.7%); among them endotoxin was found in the blood of 10 (83.32%) and in the peritoneal fluid of 8 (66.66%) patients. Renal dysfunction was found in 4 (28.57%) patients; endotoxin was present in the blood of all 4 patients and in the peritoneal fluid of 3 (75%) patients. Cardiovascular abnormality was detected in 8 (57.14%) patients, and endotoxin was present in the blood and peritoneal fluid of all patients. Metabolic abnormality was present in 8 (57.14%) patients; endotoxin was present in the blood of all 8 patients and in the peritoneal fluid of 7 (87.6%) patients. Eight (88.88%) of the 9 patients who required surgery had endotoxemia. Three (30%) patients with endotoxemia survived, whereas all 4 patients without endotoxemia survived. Mean hospital stay was 61.2 days and 46.7 days for endotoxin-positive and endotoxin-negative patients, respectively. We conclude that the presence of endotoxin in blood and peritoneal fluid correlates with the severity, systemic complications, and mortality rates of acute pancreatitis. Endotoxin estimation can identify patients at risk in the early stages of acute pancreatitis.

Natural course of acute pancreatitis

Acute pancreatitis comprises, in terms of clinical, pathologic, biochemical, and bacteriologic data, four entities. Interstitial edematous pancreatitis and necrotizing pancreatitis are the most frequent clinical manifestations; pancreatic pseudocyst and pancreatic abscess are late complications after necrotizing pancreatitis, developing after 3 to 5 weeks. Determinants of the natural course of acute pancreatitis are pancreatic parenchymal necrosis, extrapancreatic retroperitoneal fatty tissue necrosis, biologically active compounds in pancreatic ascites, and infection of necrosis. Early in the course of acute pancreatitis multiple organ failure is the consequence of various inflammatory mediators that are released from the inflammatory process and from activated leukocytes attracted by pancreatic injury. During the late course, starting the second week, local and systemic septic complications are dominant. Around 80% of deaths in acute pancreatitis are caused by septic complications. The infection of pancreatic necrosis occurs in 8% to 12% of acute pancreatitis and in 30% to 40% of patients with necrotizing pancreatitis. Bacteriologic analysis of intraoperative smears and aspirates reveals predominantly gram-negative germs deriving from the intestine, most frequently Escherichia coli. It has been confirmed that after necrotizing pancreatitis a considerable large group of patients suffer long-lasting exocrine and endocrine insufficiency.

Increased monocyte cytokine production in association with systemic complications in acute pancreatitis

Tumour necrosis factor (TNF) alpha, interleukin (IL) 1 beta, IL-6 and IL-8 are thought to play a central role in the pathophysiology of sepsis but their role in acute pancreatitis is unknown. In the present study, monocytes were isolated from the peripheral blood of 26 patients with moderate or severe acute pancreatitis without biliary sepsis. Secretion of these cytokines in vitro was measured at intervals during the first week of illness. Sixteen patients developed systemic complications. Peak TNF-alpha secretion was significantly higher in patients who developed systemic complications (median (interquartile range (i.q.r.)) 18.5 (5.5-28.5) ng/ml) than in those with an uncomplicated course (3.7 (2.3-6.4) ng/ml, P < 0.01). Similarly, peak IL-6 and peak IL-8 secretion were significantly higher in the complicated group (IL-6: complicated median (i.q.r.) 48.9 (12.1-71.0) ng/ml, uncomplicated 16.3 (14.2-37.9) ng/ml, P < 0.05; IL-8: complicated 748 (643-901) ng/ml, uncomplicated 608 (496-749) ng/ml), P < 0.05). No significant difference in peak IL-1 beta secretion was observed between the two groups. Systemic complications of acute pancreatitis are associated with a significant increase in monocyte secretion of TNF-alpha, IL-6 and IL-8 suggesting that, as in sepsis, these cytokines play a central role in the pathophysiology of the disease.

Mononuclear phagocyte activation and acute pancreatitis

Severe, acute pancreatitis is commonly associated with a systemic illness which may result in multiple organ failure. There is evidence that an aberrant immune response, involving increased secretion of proinflammatory cytokines from activated monocytes and mononuclear phagocytes, is responsible for another systemic illness--septic shock. Previous studies have investigated whether there is a correlation between plasma cytokine levels and severity of pancreatitis. However, these results may not reflect mononuclear phagocyte activation. In this paper, monocytes (collected from patients with severe pancreatitis) were cultured in vitro and secreted cytokine levels measured after 24 hours by ELISA. Secretion of tumour necrosis factor alpha, interleukin-6 and interleukin-8 was higher in cells taken from patients who later developed systemic complications. There was no difference in the secretion of interleukin-1 beta. The mechanism by which mononuclear phagocytes are activated in acute pancreatitis, and the role of genetic predisposition, are discussed.

The use of lexipafant in the treatment of acute pancreatitis

The pathophysiology of systemic organ failure in acute pancreatitis has been the subject of debate for many years but there is growing evidence that increase production of pro-inflammatory cytokines plays an important role. from this work and from the results of studies in experimental pancreatitis there exists a rationale for the use of PAF antagonists in the treatment of acute pancreatitis. Two pilot studies have now demonstrated a beneficial effect of the PAF antagonist Lexipafant on acute pancreatitis which may lead to an important advance in the treatment of these patients. A multicentre trial aiming to recruit 300 patients with severe acute pancreatitis is now underway in the UK, the results of which will be awaited with interest.

Hemodynamic effects following intraperitoneal infusion of pancreatic ascites fluid

Severe necrotizing pancreatitis is accompanied by release of hemorrhagic ascites fluid (HAF), which is thought to be related to the occurrence and frequency of cardiocirculatory and pulmonary failure as a consequence of acute pancreatitis. The purpose of this study was to evaluate the role of HAF due to these systemic complications. Experiments were performed in 25 pigs (mean b.wt. 22 +/- 1 kg) under general anesthesia and mechanical ventilation. The animals received 50 ml/kg b.wt. i.p. of either physiologic saline solution (control CO, n = 9) or hemorrhagic ascites fluid (HAF, n = 16). HAF was obtained from 16 pigs with pancreatitis induced by intraductal infusion of bile salt. Eight animals in the HAF group were pretreated with indomethacin (10 mg/kg i.v. INDO/HAF). All animals were followed up for 6 h. Mean arterial pressure, cardiac output, and stroke volume fell significantly in the HAF (-25%, -27%, -27%) and in the INDO/HAF groups (-24%, -20%, -17%) as compared with controls (-6%, -6%, -6%). Also, left ventricular end-diastolic pressure (LVEDP) decreased by 52% and 48% in both HAF recipient groups, whereas LVEDP was unchanged in the control group. Myocardial contractility (Vmax) remained unaltered in all experimental groups. No significant differences in gas exchange and lung dry/wet weight ratio were observed. Lipase and PGI2 of the unpretreated HAF group rised to 203% and 198% in arterial blood at 6 h compared with unaltered levels in the control group. No increase of prostanoid concentrations was detected in the indomethacin-pretreated group, whereas lipase increase by a comparable extent as in the HAF group. We conclude that the early consequences of HAF are mainly characterized by systemic hypotension due to hypovolemia.

Effect of naloxone on the haemodynamics and the outcome of experimental acute pancreatitis in dogs

Endogenous opioid peptides may play a role in the genesis of pancreatic damage in acute pancreatitis. The effects of naloxone on the haemodynamic changes in acute pancreatitis were investigated by inducing it in dogs with pancreatic ductal injection of fresh trypsin-bile mixture. In the control group (n = 8), acute pancreatitis was characterized haemodynamically by falls in the maximum positive and negative dP/dt (+/- dP/dt), cardiac output (CO) and cardiac index (CI), and increases in the pulmonary vascular resistance (PVR) and systemic vascular resistance (SVR) as well as an early reduction of pancreatic blood flow (PBF). In another set of eight dogs (naloxone group), naloxone was given intravenously 10 min after the induction of acute pancreatitis (80 micrograms/kg as a bolus + 80 micrograms/kg/h for 3 h). Compared with untreated dogs, naloxone significantly increased PBF and the +/- dP/dtmax; prevented the significant decreases in CO and CI and increases in PVR and SVR, and reduced significantly the severity of pancreatitis, as assessed by both the histological staging and the mortality rate. These results suggest that naloxone limits the progression of acute pancreatitis from oedematous to haemorrhagic form. It is proposed that endogenous opioid peptides may play a role in the pathophysiology of acute pancreatitis.

Early surgical débridement of symptomatic pancreatic necrosis is beneficial irrespective of infection

In order to assess the recent trend of nonoperative management of pancreatic necrosis, we reviewed 82 variables in 73 consecutive patients with symptomatic necrotizing pancreatitis. The mortality rate for the series was 25% (18 of 73). The only preintervention variables that correlated with mortality were APACHE II score greater than 15 (p = 0.01), preintervention blood transfusion (p less than 0.001), respiratory failure (p less than 0.001), and shock (p less than 0.01). Patients who developed recurrent sepsis following the initial intervention had a significantly higher mortality rate (17 of 34) than those who did not (1 of 39) (p less than 0.001). The rate of recurrent sepsis varied widely among individual surgeons and correlated with APACHE II score. The presence of infected versus noninfected necrosis did not correlate significantly with outcome. When percutaneous radiologically guided drainage was the initial therapeutic modality (n = 6), recurrent sepsis requiring surgical drainage inevitably occurred. Patients treated with percutaneous drainage (often in combination with surgical drainage) had a longer hospital stay (82 versus 42 days, p less than 0.001), spent more days in the intensive care unit (31 versus 6 days, p less than 0.001), and required more days of total parenteral nutrition (57 versus 27 days, p less than 0.001) than those treated solely by surgical means. We conclude that aggressive initial surgical débridement should be the first step in managing symptomatic pancreatic necrosis and that the presence of infection should not be the sole determinant of intervention.

Pancreatogastrostomy in experimental acute necrotizing pancreatitis

Experimental acute necrotizing pancreatitis was induced retrogradely in dogs with sunflower oil injected intraductally. Then, a zipper was sutured into the abdominal wound. From the first postoperative day, three different treatments were started: first group: only conservative therapy was used; second group: removal of necrotized tissue and single peritoneal lavage were applied; and third group: the necrotic part of the pancreas was marsupialized into the stomach. Through the systematic opening of the zipper, the abdominal cavity could easily be explored and the temporal course of disease could be observed in all animals. During this regular procedure, the amylase concentration and the amount of peritoneal exudate were determined. The blood amylase and glucose levels were also measured. On the first postoperative day, the amylase level and the amount of peritoneal exudate were high in all groups. The dogs of the pancreatogastrostomized group showed a dramatic decrease of the exudate and the most advantageous temporal course of the blood amylase level. The survival rate similarly was advantageous in the pancreatogastrostomized group.

[Acute necrotizing hemorrhagic pancreatitis]

There is no etiologic treatment for acute necrotizing pancreatitis. Advances in intensive care resulted in a reduction in early death rate by a better control of systemic complications. Delayed death rate from infection is high (20-60%). Diagnostic problems are an important cause, in spite of the aid of computed tomography and echography. The prognosis will further be improved by earlier diagnosis, a better definition of surgical treatment when complications arise, and constant medicosurgical collaboration.

[Pancreatic circulation in experimental biliary pancreatitis]

Measurements of pancreatic micro- and macrocirculation were performed to evaluate the pancreatitis-induced changes. Pigs were anesthetized and ventilated mechanically. Hypotension induced side-effects were avoided by adequate volume replacement. After laparatomy, splenectomy and gastroectomy the animals were enterotomized. Systemic hemodynamic parameters were monitored as well as pancreatic blood flow (Q), which was measured electromagnetically, and arterial and portal-venous blood gases. Pancreatic microcirculatory parameters were observed using fluorescence-videomicroscopy after i.v. administration of FITC dextran 150 and FITC labeled autologous erythrocytes. The pigs were randomly assigned to a control (n = 9) and a pancreatitis group (n = 10), the later being induced by the retrograde infusion of sodium-taurocholate. Systemic and pancreatic macrohemodynamic parameters remained constant in both groups, except for avdO2 and O2-consumption (O2-c) decreasing significantly in the pancreatitis group. At baseline 42% of all capillaries were perfused in both groups. In pancreatitis we detected focal areas with persistent stasis and areas which were continuously perfused. In these areas the portion of capillaries perfused by erythrocytes increased significantly to 67%. This was accompanied by an extravasation of FITC dextran. The finding of an unchanged Q beside reduced O2-c and avdO2 during pancreatitis is explained by the changes in pancreatic microcirculation. Focal stasis was observed beside areas showing typical signs of an acute inflammation: increased macromolecular permeability and capillary recruitment, e.g. oedema and hyperaemia.

Role of phospholipase A2 in human acute pancreatitis

In a prospective clinical trial, 85 patients with acute pancreatitis, including 50 with acute interstitial-edematous pancreatitis and 35 with necrotizing pancreatitis, were recruited. Serum pancreatic immunoreactive phospholipase A2 (IR-PLA2), serum phospholipase A catalytic activity (CA-PLA), and serum phospholipase A2 catalytic activity (CA-PLA2) were determined daily between day 1 and day 10 after the onset of the disease. The serum course of IR-PLA2 values for patients with acute interstitial-edematous pancreatitis was comparable to that for patients with necrotizing pancreatitis. In contrast, the determination of CA-PLA and of CA-PLA2 specific activity in the serum revealed a high differentiation between patients with interstitial edematous and those with necrotizing pancreatitis. The overall accuracy for differentiating patients with necrotizing pancreatitis from those with the interstitial-edematous type was 79% for CA-PLA and 77% for CA-PLA2 (cut-off level: CA-PLA, 15 U/L, day 1-5; CA-PLA2, 3.5 U/L, day 1-5). Patients with pancreatitis-associated pulmonary complications showed significantly higher CA-PLA and CA-PLA2 values in the serum. This study demonstrates the role of serum catalytic phospholipase A2 in human acute pancreatitis where the development of pancreatic necrosis and pulmonary failure is concerned.

Role of reactive oxygen metabolites in early cardiopulmonary changes of acute hemorrhagic pancreatitis

The role of reactive oxygen metabolites in extrapancreatic organ dysfunction associated with acute hemorrhagic pancreatitis was studied in dogs. Experimental pancreatitis was induced by the intraductal infusion of activated trypsin and taurocholate. Cardiac output, pulmonary and systemic blood pressure, pulmonary wedge pressure, central venous pressure, heart rate, blood gases and serum amylase were measured. Cardiac index, pulmonary and systemic vascular resistance, and the right and left stroke work were calculated. Systemic arterial and venous blood pressure and cardiac index gradually declined over 6 hr, while pulmonary mean blood pressure and pulmonary vascular resistance increased. Pretreatment of pancreatitis with catalase and superoxide dismutase prevented the rise in mean pulmonary blood pressure, moderated the rise in pulmonary vascular resistance, and decreased the rate and extent of the fall in cardiac index. These data suggest that reactive oxygen metabolites may play some role in the extraabdominal organ manifestations of acute pancreatitis.

Surgical management of necrotizing pancreatitis

The most important diagnostic step in the management of patients with severe acute pancreatitis is the discrimination between acute interstitial and necrotizing pancreatitis. Measurement of C-reactive protein, lactic acid dehydrogenase, alpha-1-antitrypsin, and alpha-2-macroglobulin and contrast-enhanced CT are useful in detecting the necrotizing course of acute pancreatitis. C-reactive protein, lactic acid dehydrogenase, and contrast-enhanced CT offer detection rates of 85 per cent to more than 90 per cent for pancreatic necrosis. Surgical decision-making in necrotizing pancreatitis should be based on clinical, morphologic, and bacteriologic data. Patients with focal pancreatic necrosis, in general, respond well to medical treatment and do not need surgery. Extended (50 per cent or more) pancreatic necroses, infected necroses, and intrapancreatic parenchymal necroses plus extrapancreatic fatty tissue necroses are indicators for surgical management. The decision for the timing of operation in patients with proved necrotizing pancreatitis should be based on clinical criteria: the development of an acute surgical abdomen, generalized sepsis, shock, persisting or increasing organ dysfunction, or some combination thereof despite maximum intensive care treatment for at least 3 days. Major pancreatic resection for the treatment of necrotizing pancreatitis appears disadvantageous. Necrosectomy and continuous local lavage allow debridement of devitalized tissue and preservation of vital pancreatic tissue. Postoperative local lavage thus results in an atraumatic evacuation of necrotic tissue, the bacterial material, and biologically active substances. The hospital mortality rate of patients treated with necrosectomy and continuous local lavage (the Ulm protocol) is below 10 per cent. Nevertheless, controlled prospective clinical trials should be performed in order to bring more precision to our clinical decisions in respect to the role of surgery for this disease.

Effect on hemodynamics of therapeutic infusion of gabexate mesilate (FOY) in experimental acute pancreatitis

Acute pancreatitis was induced in ten anesthetized dogs by retrograde injection for bile mixed with trypsin into the pancreatic duct. Five animals were treated with i.v. infusion of gabexate mesilate in a dose of 1 mg/kg per hour. Hemodynamic data were regulary monitored during a 10-h observation period. Cardiac output (CO), mean arterial pressure (MAP), and left ventricular stroke volume (LVSV) decreased rapidly in untreated animals. An increase of systemic vascular resistance (SVR) and pulmonary vascular resistance (PVR) was observed in dogs without treatment. Gabexate mesilate given as a therapy significantly improved the hemodynamic parameters. The study demonstrates an advantageous influence of synthetic antiprotease gabexate mesilate on the course of acute experimental pancreatitis.